


Mer-Mystery

by Sephypsycologist



Category: Undertale (Video Game)
Genre: It's a good thing, Other, Polyamory
Language: English
Status: Completed
Published: 2018-12-13
Updated: 2018-12-13
Packaged: 2019-09-17 17:06:05
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 862
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16978551
Author URL: https://archiveofourown.org/users/Sephypsycologist/pseuds/Sephypsycologist
Summary: Sans and Red wake in the middle of the night to their tiny lover....sleepwalking?





	Mer-Mystery

Red was the one who woke Classic up. “hey, hey, classic, you need to get up.”

“whuh?” Sans lifted his head, eye lights coming back into focus once they popped into being. “why?”

“cause our babe just up and left,” Red hissed, pointing to the empty kleenex-box bed between their mattresses.

Sans hopped to his feet and opened the door to the bedroom, Red behind him as they searched for the presence of their tiny lover.

“Where could they be going?” Sans mutters as they spot the tiny footprints in the sand in front of their beach house.

“dunno, but we need to see. when i saw them walking out, it was like they were in a trance. didn’t answer me, didn’t react to anything i did,” Red replied, having caught up with them and gesturing to show Classic what he meant.

Their lovely tiny was glassy eyed and limp in the arms, walking forward slowly toward a large cave by the waterside.

“what do we do?” Sans whispered, suddenly frozen with indecision.

“we watch. it’s dangerous to wake a sleep walker, y’know. least that’s what boss says,” Red replied, equally as quiet. “we’ll only do somethin’ if they’re gonna hurt themselves.”

So, two skeletons walked down the beach in bare feet, following a miniature human into a sea cave beneath the light of a full moon.

The slick coolness of the rocks felt odd on their bones, and watching their human making their way so far inside gave them shivers.

Just at the center of a larger cavern than the entrance, there was a deep pool, and a hole in the ceiling that let in the shimmering moonlight. Sans and Red, amazed at the sight, took their eyes off the human long enough that by the time they looked back, they couldn’t react in time to stop them from jumping into the pool.

“sans!” Red pulled him with him to the edge of the pool, “we gotta get them outta there? can you swim?”

“no, i’m just as boney as you!” the skeleton panicked, “I can’t even feel their soul right now.”

Red was about to shout at his double when pearly bubbles formed in the middle of the pool along with a rainbow glow. The two focused on it and were amazed with out of the middle came their tiny love, now a mystical mermaid.

They swam over with deep shame written on their brow, barely able to look at either of them, “I….I guess you saw all of that.” Their soaked pajama shirt clung to their body in awkward wrinkles.

“babe, we were scared to death,” Red responded, disbelieving. “we thought we just saw ya drown y’rself.”

“I didn’t….I thought you would both be asleep by now.” They whimpered, sinking up to their chest in the water. “I didn’t want you to know.”

“how long has this gone on, cutie?” Sans murmured, making Red turn to look at him.

“I’ve always done this. I’m…I’m supposed to be a mermaid but I found a spell to let me live on land. It….it made me happy to be on land. And I met both of you here,” they sighed. “But every full moon, no matter where I am, I have to return here for a night and be my real self again.”

“Then why didn’t ya tell us, babe? if we knew, we coulda just let you do your thing and not worry,” Red asked. He was baffled. Why would they keep this from them?

They’re face crumpled up, “I thought you’d leave me if you knew I couldn’t travel. I can’t….I can’t ever move away from here or I’ll turn to sea foam. I’ll die. And you both have a whole planet to explore!” Tears, thick and syrupy, began to trail down their cheeks, “A-and your brothers are out there, expecting you to come home any day now and….I can’t…I’ll never be able to see any of that with you. Once a month, I have to be here.”

Sans and Red glanced at each other, then stuck their hands in the water to comfort their amazingly magical datemate. Cooing softly, Sans rubbed their back while Red held their hands, “babe, we weren’t planning on leaving you either way. And a month is plenty of time for you to come meet our bros and us to get you back here. you were panicking again.”

“I know but!” they started, and Red cut them off.

“but nothin’, sweetheart. we love ya, no matter what. and if stayin’ here is what keeps you safe and happy, then we’ll do it. i always fancied bein’ a beach bum, y’know,” he winked, and they laughed brokenly.

“what he said,” Sans chuckled, “you’re our everything now, and we can always take turns seeing the world. there’s no rush. it’s not going anywhere and neither are we.”

the mermaid leaned into their gentle touches gratefully. The skeletons, glad to finally know the mystery of the sleepwalker, spent their night by the side of the pool, and all three went back to their cozy home in the first of dawn’s light.


End file.
